Constants part a two small charged spheres are 9.20 cm apart. they are moved, and the force on each of them is found to have been tripled how far apart are they now? express your answer to three significant figures and include the appropriate units.

5.3 cm

Explanation:

Let the charges on the spheres be q and Q.

r = 9.20 cm

F = k Q q / (9.20)^2 (1)

Let the new distance be r' and force F'

F' = 3 F

F' = k Q q / r'^2

3 F = k Q q / r'^2 (2)

Divide equation (1) by (2)

F / 3 F = r'^2 / 84.64

1 / 3 = r'^2 / 84.64

r' = 5.3 cm

think its the third option

this is poiselle's equation from fluid mechanic in physics. mech eng